Visible-light-driven CO₂reduction on dye-sensitized NiO photocathodes decorated with palladium nanoparticles

Abstract

(A) Cross-section view of the stack of active layers constituting a hybrid photocathode for CO2 reduction. (B) Structure of dye P1 sensitizing the NiO semiconductor. (C) Energy-level matching between components of the modified photocathode.

Photoelectrochemical Reduction of CO2 at Poly(4‐Vinylpyridine)‐Stabilized Copper(I) Oxide Semiconductor: Feasibility of Interfacial Decoration with Palladium Cocatalyst

“…As mentioned earlier, an important step in the preparation of the Cu 2 O/P4VP‐based photocathodes for CO 2 RR is the deposition of catalytic nanoparticles (nPds). Although they typically have diameters from 6 to 10 nm, [ 69,70 ] following deposition onto Cu 2 O/P4VP they tend to form agglomerates (Figure 3). Figure shows cyclic voltammetric responses for nPds (loading, 100 μg cm −2 ) immobilized on FTO electrode substrate covered with a) P4VP (solid line), b) Cu 2 O (dashed line), and c) Cu 2 O/P4VP (dotted line); they have been recorded in the deoxygenated (argon‐saturated) (Figure 5A) and in the CO 2 ‐saturated 0.1 mol dm −3 Na 2 SO 4 (Figure 5B) electrolytes.…”

“…Decoration of the P4VP‐modified Cu 2 O photoelectrode with nPds should result in the formation of CO as the reaction product. [ 53,70 ] Because the Pt‐based voltammetric‐stripping oxidation experiment does not permit clear distinction of CO from other small organic molecules including methanol, ethanol, or even formic acid, the additional stripping experiments have been performed using the adjacent GC working electrode with deposited palladium nanoparticles. Furthermore, the stripping experiments have been in the near‐neutral deoxygenated sodium sulfate solution: under such conditions, some distinction between the oxidations of carbon monoxide and methanol is feasible.…”

Enhancement of Activity of Copper Sites Toward Electroreduction of Carbon Dioxide through Hierarchical Deposition of Metal Oxide Cocatalysts

“…To drive successfully electrochemical CO2RR, many catalytic metals have been considered. For example, Pb, Hg, Tl, In, Sn, Cd and Bi yield primarily are formate; Pt, Fe, Ti and Ni tend to induce mostly hydrogen evolution; whereas Au, Ag, Zn, Ga and Pd are the CO-producing metals (15)(16)(17)(18). In this respect, the copper based catalysts have unique properties permitting reduction of carbon dioxide to CxHyOz-type oxo-hydro-carbons (e.g., alcohols, aldehydes) and hydrocarbons with reasonable Faradaic efficiencies.…”